Buccarelli was appointed Viceroy of Mexico, and retired on the fourth of August, 1771. He had proved a worthy successor of the much esteemed Count Ricla and left behind him an excellent reputation. It was said of him that he had never once lacked that political prudence which should ever guide the actions of an official in such a responsible position as was the governorship of Cuba. He was praised for his cautious inquiries into legal abuses and his judicious settlement of cases, some of which had for forty years occupied the time of the courts and filled the pockets of greedy attorneys. He was reported under the most exasperating circumstances to have always conserved his affable disposition and to have never lost his temper, however great may have been the provocation. Upon the whole, he was looked upon as a man of rare nobility of character and Cuba was loath to part with him. He was one of the few governors that had never given cause for any complaint. This was attested by the Minister of the Indies, then Baylio Knight Julian de Arriaga, who wrote to him by order of His Majesty that not the slightest complaint of his government had come to the court.
While Cuba was enjoying the peace and prosperity which had followed its return to Spain, Louisiana, which by the Treaty of Paris had been ceded to Spain by Louis XV. of France, to indemnify her for the Floridas and the government of which was annexed to that of Cuba, was going through a most harassing period of anxiety. For this agreement, which transferred the French inhabitants of Louisiana to Spain, was a violation of that human right which at this very time was beginning to dawn in the awakening political consciousness of mankind, and was to be a source of serious conflicts between the French of Louisiana and the authorities that came to establish upon her soil the rule of the king of Spain.
Bancroft gives an interesting account of the events that occurred. He writes in his "History of the United States" (Vol. IV, p. 122):
"The Treaty of Paris left two European powers sole sovereigns of the continent of North America. Spain, accepting Louisiana without hesitation, lost France as her bulwark, and assumed new expenses and dangers, to keep the territory from England. Its inhabitants loved the land of their ancestry; by every law of nature and human freedom, they had the right to protest against the transfer of their allegiance."